CN1955198A - Catalyst component for ethylene polymerization and its preparation method - Google Patents

Catalyst component for ethylene polymerization and its preparation method Download PDF

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Publication number
CN1955198A
CN1955198A CN 200510114546 CN200510114546A CN1955198A CN 1955198 A CN1955198 A CN 1955198A CN 200510114546 CN200510114546 CN 200510114546 CN 200510114546 A CN200510114546 A CN 200510114546A CN 1955198 A CN1955198 A CN 1955198A
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titanium
compound
magnesium
catalyst
ethylene polymerization
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CN100532405C (en
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高克京
王洪涛
吕新平
陈伟
王仪森
王如恩
赵勤芳
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Sinopec Beijing Research Institute of Chemical Industry
China Petroleum and Chemical Corp
China Petrochemical Corp
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Sinopec Beijing Research Institute of Chemical Industry
China Petroleum and Chemical Corp
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Abstract

This invention relates to a catalyst composition of etileno polymerization or copolymerization and its preparation, it is through that in the solvent of liquidness alkanes, carboxylic ester compound is mixed with Dialkyl Magnesium compound of which general formula is MgR1R2, among them R1, R2 is the same or different alkyl group which contains 1-20 carbon atom, the above-mentioned mixed liquor reacts with compound that contains chlorine, obtain catalyst composition that contains titanium by drying; Prepared catalyst is suitably used for slurry method and polymerization technology of gaseous phase method, especially suitably used for polymerization technology of slurry method.

Description

Be used for ethylene polymerization catalysts component and preparation method thereof
Technical field
The present invention relates to a kind of particularly component and preparation method thereof of the Ziegle-Natta support of the catalyst of vinyl polymerization of alkene that is used for, and with the method and the Application of Catalyst of preparing carriers catalyzer.
Technical background
As everyone knows, the Ziegler-Natta catalyst system is to be made of together as promotor at least a transition metal (as titanium) compound and at least a metal (as aluminium) organic compound.When the magnesium chloride solids mineral compound used jointly as compounds such as carrier and titaniums, activity of such catalysts exceeded much than the simple activity of titanium compound of using, and the character of magnesium chloride support and preparation method are most important to the performance of catalyzer.Because the vital role of magnesium chloride aspect the preparation Ziegler-Natta catalyst, current widely used Ziegler-Natta catalyst contains the magnesium chloride composition mostly.The method of introducing magnesium chloride in the catalyst preparation process mainly contains two kinds, and a kind of is directly to use magnesium chloride, dissolves the suspension pickling process of back use etc. with polar solvent as the common polishing of previously used titanium compound and magnesium chloride solids, with magnesium chloride; Another kind is to form magnesium chloride by reaction, as compound and chlorination reagent reaction formation magnesium chlorides such as use organic-magnesiums.These the two kinds existing a large amount of patents of method for preparing catalyst of introducing magnesium chloride are delivered, but owing to use the method difference of magnesium chloride, each is variant between the different patents of different company, and its relative merits are also respectively arranged.
For example, among the CN1085569, be that Magnesium Chloride Anhydrous and Fatty Alcohol(C12-C14 and C12-C18) such as isooctyl alcohol are reacted, form homogeneous solution, add organo-aluminium compound again and separate out precipitation, then with a large amount of titanium tetrachlorides dippings, the finally catalyzer of making.But in the Preparation of catalysts process, the solvent temperature of magnesium chloride needs 120~140 ℃ high temperature, and use high carbon chain alkane such as decane to be solvent in a large number, difficult solvent recovery, in addition, a large amount of titanium tetrachlorides that use cause corrosion to equipment easily in catalyst preparation process, and production environment is impacted.
Chinese patent ZL91111840 discloses a kind of Preparation of catalysts method, this method is used alkyl magnesium compound, is not had reactive hydrogen and do not have the electron donor of ester functional group and the carrier that chlorination reagent has prepared a kind of magnesium chloride, this carrier can prepare the catalyzer of high titanium content, the size-grade distribution of catalyzer is also narrower, though this patent claims the catalyzer for preparing that very high ethylene polymerization activity is arranged, but find that by contrast the catalyst activity of its final preparation is lower than the catalyst activity among the CN1085569.
In order to overcome the weak point of prior art, the invention provides a kind of component that is used for ethylene rolymerization catalyst and preparation method thereof, comprising the preparation method of support of the catalyst and the preparation method of catalyst component.The catalyst activity height of gained, narrow particle size distribution, the preparation method is simple, and is low for equipment requirements, and environmental pollution is little.The catalyzer of preparation is applicable to slurry process and vapor phase process polymerization technique, is particularly useful for slurry polymerization technology.
Summary of the invention
A kind of ethylene polymerization catalysts component that is used for of the present invention, it is by in liquid hydrocarbon solvent, is MgR with carbonate and general formula 1R 2Dialkyl magnesium compound mixes, wherein R 1, R 2Be the identical or different alkyl that contains 1~20 carbon atom, above-mentioned mixed solution and chlorine-containing compound reaction are separated out precipitation, obtain support of the catalyst through washing, drying; With gained support of the catalyst and titanium-containing compound reaction, obtain titaniferous catalyst component through washing, drying;
Described titanium compound general formula is Ti (OR 4) 4-mX m, R in the formula 4Be C 1~C 14Aliphatic group, X is F, Cl, Br, m is 1~4 integer.Be selected from a kind of in titanium tetrachloride, titanium tetrabromide, titanium tetra iodide, four titanium butoxide, purity titanium tetraethoxide, a chlorine triethoxy titanium, dichloro diethoxy titanium, trichlorine one ethanolato-titanium, the titanous chloride or their mixture, preferred titanium tetrachloride.
The present invention is used for the ethylene polymerization catalysts component, described dialkyl magnesium compound with mixes as the carbonate of giving electron compound after, react with chlorine-containing compound again and separate out carrier.Wherein dialkyl magnesium compound is selected from a kind of in di-n-butyl magnesium, normal-butyl sec-butyl magnesium, di-isopropyl magnesium, di-n-hexyl magnesium, sec.-propyl normal-butyl magnesium, ethyl n-hexyl magnesium, ethyl normal-butyl magnesium, di-n-octyl magnesium or the butyl octyl magnesium.The preferred di-n-butyl magnesium of the organic-magnesium that uses in the reaction, ethyl normal-butyl magnesium or butyl octyl magnesium.
The present invention is used for the ethylene polymerization catalysts component, one of key that is used to prepare carrier is to select suitable electron donor compound, different electron donor compounds is bigger to the particle form influence of the carrier of generation, the inventor is by discovering repeatedly, use carbonate, and the mol ratio of suitably regulating carbonate and alkyl magnesium compound can prepare the ball type carrier of good particle form, the example of carbonate has hydroxyethyl methylacrylate, ethyl propenoate, ethyl acetate, ethyl benzoate, the o-toluic acid ethyl ester, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diamyl phthalate etc., wherein preferred fragrance ester compound, most preferably bialkyl ortho phthalate compound.
The mol ratio of carbonate and alkyl magnesium compound is very big to the balling ratio influence of carrier, be the preparation ball type carrier, in every mole of alkyl magnesium compound, the molar ratio range of carbonate and alkyl magnesium compound is 0.2~2, preferred 0.2~1, most preferably 0.3~0.55.
The present invention is used for the ethylene polymerization catalysts component, and described chlorine-containing compound is meant the compound that can generate magnesium chloride with the dialkyl magnesium compound reaction.Be selected from 1-chlorobutane, n-propyl chloride, monochloroethane, 2-chloroheptane, 3-chloroheptane, Sec-Butyl Chloride, 2 cbloropropane isopropyl chloride, tertiary butyl chloride, 2,2-dichlorobutane, 2,2-propylene dichloride, 1, a kind of in 3-dichlorobutane, aluminum chloride, boron trichloride, silicon tetrachloride, titanium tetrachloride, tetrachloromethane, the hydrogenchloride, preferred silicon tetrachloride or titanium tetrachloride.
The chlorine in the chlorine-containing compound and the mol ratio of dialkyl magnesium compound are also extremely important to the preparation ball type carrier, be the preparation ball type carrier, in every mole of dialkyl magnesium compound, the chlorine in the chlorine-containing compound and the mol ratio of dialkyl magnesium compound are 1.0~20, preferred 2~15, most preferably 6~10.
The preparation feedback of support of the catalyst of the present invention is chosen in the hydrocarbon medium and carries out.Preparation feedback preferably carries out in nonpolar inertia hydrocarbon medium, and preferred nonpolar medium can be an alkane, for example pentane, hexane, iso-pentane, normal heptane, octane, nonane and decane etc.Before use, be used for liquid medium of the present invention and preferably should be purified, for example with silica gel or molecular sieve diafiltration, to remove minor amount of water, oxygen, polar compound and other are unfavorable for the material of catalyst activity.
The method that preparation of the present invention is used for ethene polymerization catalyst component comprises the preparation of support of the catalyst and support of the catalyst and titanium-containing compound is reacted the preparation that obtains catalyst component.The preparation of support of the catalyst is a kind of precipitin reaction of under agitation carrying out in liquid hydrocarbon solvent.In this precipitin reaction, the working conditions of various physical parameters such as system viscosity, stirring type, stir speed (S.S.), reactant plays very important effect in the granularity of controlling carrier and size-grade distribution, yet obtain support of the catalyst of the present invention, the selection of the reactant especially selection of electron donor compound is extremely important.By selecting carbonate for use, and adopt slower reaction process and long reaction times, can obtain the spherical carrier of catalyst of better particle form.Therefore, except selected reactive component, preferably select lower temperature of reaction and long reaction times for use.Temperature of reaction among the present invention is generally at 15~100 ℃, and preferred 25~50 ℃, it is 0.5~48 hour that the reaction times is generally, preferred 2~16 hours.
The above-mentioned support of the catalyst that obtains with transition metal titanium compound dip treating, can be obtained being used for the ethylene polymerization catalysts component.
The titanium compound dipping reaction of support of the catalyst is carried out in the liquefied hydrocarbon medium, and hydrocarbon medium comprises nonpolar mediums such as toluene, chlorobenzene, chloroparaffin isopolarity medium and pentane, hexane, heptane.The consumption of titanium compound is 1.0~25 moles of every mole of magnesium chloride, is preferably 2~20 moles, and in addition, recommending the temperature of dipping reaction is 20~130 ℃, preferred 20~120 ℃.In fact, be the catalyst performance that obtains expecting, the dipping reaction can be carried out one or many.
The invention still further relates to a kind of catalyst system that is used for vinyl polymerization or copolymerization, it contains above-mentioned catalyst component of the present invention and basic aluminum compound is arranged, and the wherein used general formula that basic aluminum compound is arranged is AlR  3, R  is C identical or inequality 1-8Alkyl, one of them or two alkyl can be replaced by chlorine, can select for use one or more aluminum alkyls mix to use, preferred AlEt 3, Al (I-Bu) 3, Al (n-C 6H 13) 3, Al (n-C 8H 17) 3, AlEt 2Cl etc.
The catalyst system that the present invention relates to is applicable to the equal polymerization of various ethene or the copolymerization of ethene and other alpha-olefins, and wherein alpha-olefin adopts a kind of in propylene, butylene, amylene, hexene, octene, the 4-methylpentene-1.
Compared with the prior art the present invention has following advantage:
The invention provides a kind of component that is used for ethylene rolymerization catalyst and preparation method thereof, comprising the preparation method of support of the catalyst and the preparation method of catalyst component.The catalyst activity height of gained, narrow particle size distribution, the preparation method is simple, and is low for equipment requirements, and environmental pollution is little.The catalyzer of preparation is applicable to slurry process and vapor phase process polymerization technique, is particularly useful for slurry polymerization technology.
Embodiment
Embodiment 1
Under the nitrogen protection; (concentration is 1M to get the n-heptane solution of 150ml dibutylmagnesium; U.S. Aldrich company product); mix with the dibutyl phthalate of 75mmol at normal temperatures, slowly drip in the reactor that the 86ml silicon tetrachloride is housed then, be warming up to 36~40 ℃; stirring reaction is 10 hours under this temperature; filter, use hexane thorough washing 6 times, the dry magnesium chloride support that gets of drum nitrogen.
Support of the catalyst is suspended in the 100ml normal hexane, drip the 33ml titanium tetrachloride, suspension is heated to 60 ℃ then, continuing stirring reaction under this temperature after 2 hours, cool the temperature to 20 ℃ while stirring, stop to stir, remove supernatant liquor, each 100ml hexane washing catalyst 4 times, drum nitrogen exsiccant catalyst fines used.
Evaluating catalyst: carry out the slurry polymerization of ethene in the stainless steel stirring tank, polymerizing condition is as follows: 2L stainless steel stirring tank, and the 1L hexane, polymerization temperature: 80 ℃, poly-and stagnation pressure: 0.73MPa, P H 2 / P C 2 H 4 = 0 . 28 / 0.45 The about 8mg of catalyst levels, the hexane solution of 1m1 triethyl aluminum (1M), polymerization time: 2 hours.
Polymerization result is shown in table 1
Embodiment 2
Dibutyl phthalate among the embodiment 1 is replaced with dimethyl phthalate, and other conditions are with embodiment 1.
The slurry polymerization appreciation condition of catalyzer is with embodiment 1, and polymerization result sees Table 1.
Embodiment 3
Silicon tetrachloride consumption among the embodiment 1 is adjusted into 150ml, and other conditions are with embodiment 1.
The slurry polymerization appreciation condition of catalyzer is with embodiment 1, and polymerization result sees Table 1.
Embodiment 4
Silicon tetrachloride among the embodiment 1 is replaced with titanium tetrachloride with mol ratio, and other conditions are with embodiment 1.
The slurry polymerization appreciation condition of catalyzer is with embodiment 1, and polymerization result sees Table 1.
Embodiment 5
Dibutyl phthalate among the embodiment 1 is replaced with ethyl acetate with mol ratio, and other conditions are with embodiment 1.
The slurry polymerization appreciation condition of catalyzer is with embodiment 1, and polymerization result sees Table 1.
Embodiment 6
Dibutyl phthalate among the embodiment 1 is replaced with ethyl benzoate with mol ratio, and other conditions are with embodiment 1.
Table 1
Active gPE/gcat Tap density g/cm 3 Resin size distributes
Greater than 20 orders 20~100 orders 100~200 orders Less than 200 orders
Embodiment 1 49000 0.31 7.7 65.1 26.0 1.2
Embodiment 2 42111 0.33 9.5 80.8 8.1 1.3
Embodiment 3 48333 0.32 12.9 75.8 9.2 1.7
Embodiment 4 39300 0.26 20.5 33.2 32.7 13.6
Embodiment 5 25000 0.17 19.6 37.6 17.7 25.1
Embodiment 6 21810 0.19 28.7 23.5 26.5 21.3

Claims (13)

1, a kind of ethylene polymerization catalysts component that is used for is characterized in that,
(1) in liquid hydrocarbon solvent, be MgR with carbonate and general formula 1R 2Dialkyl magnesium compound mixes, wherein R 1, R 2Be the identical or different alkyl that contains 1-20 carbon atom, above-mentioned mixed solution and chlorine-containing compound reaction are separated out precipitation, obtain support of the catalyst through washing, drying;
(2) with the gained support of the catalyst with contain transition metal titanium compound reaction, obtain titaniferous catalyst component through washing, drying;
The described transition metal titanium compound general formula that contains is Ti (OR 4) 4-mX m, R in the formula 4Be C 1~C 14Aliphatic group, X is F, Cl, Br, m is 1~4 integer.
2, the ethylene polymerization catalysts component that is used for according to claim 1, it is characterized in that described dialkyl magnesium compound is selected from a kind of in di-n-butyl magnesium, normal-butyl sec-butyl magnesium, di-isopropyl magnesium, di-n-hexyl magnesium, sec.-propyl normal-butyl magnesium, ethyl n-hexyl magnesium, ethyl normal-butyl magnesium, di-n-octyl magnesium or the butyl octyl magnesium.
3, the ethylene polymerization catalysts component that is used for according to claim 2 is characterized in that, described dialkyl magnesium compound is di-n-butyl magnesium, ethyl normal-butyl magnesium or butyl octyl magnesium.
4, the ethylene polymerization catalysts component that is used for according to claim 1 is characterized in that, described carbonate is the aromatic esters compound.
5, the ethylene polymerization catalysts component that is used for according to claim 4 is characterized in that, described carbonate is the bialkyl ortho phthalate compound.
6, the ethylene polymerization catalysts component that is used for according to claim 1, it is characterized in that, described chlorine-containing compound is selected from 1-chlorobutane, n-propyl chloride, monochloroethane, 2-chloroheptane, 3-chloroheptane, Sec-Butyl Chloride, 2 cbloropropane isopropyl chloride, tertiary butyl chloride, 2,2-dichlorobutane, 2,2-propylene dichloride, 1, a kind of in 3-dichlorobutane, aluminum chloride, boron trichloride, silicon tetrachloride, titanium tetrachloride, the tetrachloromethane hydrogenchloride.
7, the ethylene polymerization catalysts component that is used for according to claim 6 is characterized in that, described chlorine-containing compound is silicon tetrachloride or titanium tetrachloride.
8, the ethylene polymerization catalysts component that is used for according to claim 1, it is characterized in that described titanium compound is a kind of in titanium tetrachloride, titanium tetrabromide, titanium tetra iodide, four titanium butoxide, purity titanium tetraethoxide, a chlorine triethoxy titanium, dichloro diethoxy titanium, trichlorine one ethanolato-titanium, the titanous chloride or their mixture.
9, the ethylene polymerization catalysts component that is used for according to claim 8 is characterized in that, described titanium compound is a titanium tetrachloride.
10, any one described preparation method who is used for the ethylene polymerization catalysts component in the claim 1~9 is characterized in that, comprises the steps:
(1), in liquid hydrocarbon solvent, under 15~100 ℃ of temperature, be MgR with carbonate and general formula 1R 2Dialkyl magnesium compound mixes, wherein R 1, R 2It is the identical or different alkyl that contains 1~20 carbon atom;
(2), under 15~100 ℃ of temperature, precipitation was separated out in mixed solution that step (1) is obtained and chlorine-containing compound reaction in 0.5~48 hour, after filtration, washing, drying obtain support of the catalyst;
(3) under 20~130 ℃ of temperature, the support of the catalyst that obtains is suspended in the varsol, with titanium-containing compound reaction, after filtration, washing, drying obtain the titanium-containing catalyst component.
11, the method that is used to prepare catalyst component according to claim 10, it is characterized in that, the mixing temperature of carbonate and dialkyl magnesium compound is 25~50 ℃ in the step (1), and the temperature of reaction in the step (2) is 25~50 ℃, and the reaction times is 2~16 hours.
12, a kind of catalyzer that is used for vinyl polymerization or copolymerization, it comprises the reaction product of following component:
(a) the described ethylene polymerization catalysts component that is used for of one of claim 1-9;
(b) at least a general formula is AlR nX 3-nOrgano-aluminium compound, R is that hydrogen or carbonatoms are 1~20 alkyl in the formula, X is a halogen, n is the number of 1<n≤3.
13, the application of the described catalyst component of claim 12 in vinyl polymerization or copolymerization.
CNB2005101145460A 2005-10-26 2005-10-26 Catalyst component for ethylene polymerization and its preparation method Active CN100532405C (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102482376A (en) * 2008-12-31 2012-05-30 陶氏环球技术有限责任公司 Random propylene copolymer compositions, articles and process
CN103130926A (en) * 2011-11-29 2013-06-05 中国石油化工股份有限公司 Catalyst carrier used for olefin polymerization and preparation method thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102482376A (en) * 2008-12-31 2012-05-30 陶氏环球技术有限责任公司 Random propylene copolymer compositions, articles and process
CN102482376B (en) * 2008-12-31 2014-04-02 陶氏环球技术有限责任公司 Random propylene copolymer compositions, articles and process
CN103130926A (en) * 2011-11-29 2013-06-05 中国石油化工股份有限公司 Catalyst carrier used for olefin polymerization and preparation method thereof
CN103130926B (en) * 2011-11-29 2015-09-16 中国石油化工股份有限公司 A kind of support of the catalyst for olefinic polymerization and preparation method thereof

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